The invention relates to a starting device, in particular a freely disengaging starting device, with an electric motor, the rotor of which drives, via a free-wheeling clutch, a driven shaft which has a pinion for the drive of an internal combustion engine gear ring. In this starting device the end section of the driven shaft which carries the pinion is supported in a front face of the housing (DE-OS 39 08 870 ).
In motor vehicle technology, such starting devices are used for starting the vehicle engines. For the starting procedure, a pinion of the starting device moves into mesh with the engine gear ring. For the required axial movement of the pinion, a driven shaft which carries it is supported so as to be axially movable. When the starting procedure is complete, the pinion disengages from the gear ring, whereupon the driven shaft returns to its starting position. The axial movement of the driven shaft takes place preferably via a coarse pitch helix. A free-wheel device is further provided which effects a torque transmission in one direction of rotation and a disengagement in the other direction, so that after the engine has started, an "overrun" of the starting device is possible, resulting in a withdrawal of the pinion.
Due to the system for the axial displacement of the driven shaft and for the free-wheel arrangement and the required support points, the resulting physical length of such starting devices is relatively large, and becomes even larger, if they are configured as gear starters.